The invention relates to a method of manufacturing a bicycle fork comprising a tubular steering spigot of metal, in particular of steel, a fork head consisting of fiber reinforced plastic and rotationally fixedly connected to the steering spigot, two fork arms which are formed in one piece with the fork head and which likewise comprise fiber reinforced plastic, and connection spigots of axle mounts of metal, in particular of steel, which are inserted in rotationally fixed manner into the free end of each of the fork arms, wherein the fork head and the fork arms have a plurality of sheaths of polymer impregnated fiber bundles which are laid around their axes and which consist either of only one group of fibers which extend parallel to one another and to the axis, or of two groups of fibers which extend parallel to one another and which can be arranged at an angle of up to 90.degree. to one another. Furthermore the invention relates to a bicycle fork made in accordance with this method.
It is already known from EP-A 0 127 553 to manufacture the tubes of a bicycle frame of sheaths or layers which are concentric to one another and which consist of polymer impregnated fiber arrangements. The fiber arrangements can be of differing construction in the individual sheaths and both sheaths with fibers extending parallel to the axis and to one another and also sheaths with fiber meshes and/or fiber fabrics can be provided. After the individual sheaths have been wound on top of one another the blanks are heated in suitable molds whereby the plastic impregnation first becomes liquid and then flows together with the plastic impregnations of the adjacent sheaths and subsequently hardens. The customary hardening temperatures lie around 20.degree. to 160.degree. C.
It has already become known (EP-A 0 230 839) to manufacture the fork head and the fork arms of bicycle forks of synthetic resin reinforced by textile material. The textile material which serves for the reinforcement consists at least partially of weaves arranged above one another and comprising fibers which extend in two different directions, with filaments or fibers which extend in the longitudinal direction being arranged between these weaves. The manufacture of the known bicycle fork proceeds in such a way that the fork head and the fork arms of resin reinforced with textile material are first manufactured in their final form including hardening and that the tubular steering spigot of metal and also the axle mounts are subsequently applied to the basic body of plastic. A firm bond between the metal and plastic parts which takes account of all possible loadings is however not achievable with the known method, or only with a high degree of complexity and expense so far as the assembly is concerned. As the receiving bores in the steering spigot and also in the lower ends of the fork arms generally have a circular cross-section the rotational securing of the metal and plastic parts relative to one another is in particular problematic.